Nutritional Status and Prevalence of Obesity in Primary-School Children and Its Association With Physical Activity Level

Childhood overweight and obesity represent a growing public-health challenge worldwide, but data from Bosnia and Herzegovina are limited. This cross-sectional study assessed the nutritional status of 5,678 primary-school pupils (2,853 boys and 2,825 girls) in Sarajevo Canton by measuring height and weight, classifying body-mass index (BMI) with WHO growth charts and grouping weekly extra physical activity into ≥ 3 h or ≤ 2 h outside regular physical-education lessons. Normal body mass was recorded in just over half of the children (50.6 %), while 22.7 % were overweight, 18.2 % obese and 8.3 % below the normal range; only one child in three met the ≥ 3 h activity threshold. Chi-square testing showed no significant dependence between BMI category and physical-activity group, and Spearman’s correlation revealed no meaningful monotonic relationship between raw BMI values and weekly activity hours. Although a high prevalence of excess body mass was confirmed, the anticipated inverse association with reported physical-activity level was not observed. The findings highlight the need for more nuanced, longitudinal research—incorporating objective activity tracking, dietary assessment and narrower age bands—to clarify the complex interplay of behavioral and environmental factors influencing childhood obesity in the Bosnian context.